Agriculture is the largest consumer of water in the world and therefore responsible for a large part of the water scarcity in the world. Still, global food demand continues to increase, due to growing populations and changing diets.
Meeting growing food demands while simultaneously shrinking the water footprint (WF) of agricultural production is one of the greatest societal challenges.
In a study, researchers La Zhuo (Twente Water Centre, University of Twente), Mesfin M. Mekonnen ( Robert B. Daugherty Water for Food Global Institute, University of Nebraska) and Arjen Y. Hoekstra (Institute of Water Policy, Lee Kuan Yew School of Public Policy, National University of Singapore) explore which environmental factors should be distinguished when determining benchmark levels for the consumptive WF of winter wheat production in China.
The consumptive WF of crops, the consumption of rainwater stored in the soil (green WF), and the consumption of irrigation water (blue WF) over the crop growing period varies spatially and temporally depending on environmental factors like climate and soil.
Farmers, generally lack incentives for saving water, since they pay little for their water use compared to other input factors. Therefore WF benchmarks serve as a useful parameter for governments, farmers and customers to reduce water consumption i.e better “crop per drop.”
Research in developing benchmark levels for the consumptive WF of crop production is still in its infancy. An important question that has been insufficiently addressed is which environmental factors should play a role when developing such benchmarks.
The study acknowledges that WF benchmarks of crop production could be global, but would preferably be context-specific, given the fact that the WF of growing a crop varies as a function of environmental factors such as climate and soil.